refactor(cache): redesign cache system with structured keys and improved performance

- Add repo_path parameter to cached_response and cached_vec_response functions
- Implement structured cache key format with namespace, repo_path, and request proto
- Replace global cache with Moka in-memory cache using weight-based eviction
- Set 256MB memory cap with 10-minute TTL and 2-minute TTI policy
- Add metrics collection for cache operations and evictions
- Implement efficient repo-scoped invalidation using key structure
- Add detailed documentation comments explaining cache architecture
- Remove outdated dependencies and update dependency versions
- Add error handling for encoding failures in cache operations
- Optimize Vec responses with length-delimited encoding and pre-allocation

merge/do_merge.rs

@@ -7,7 +7,10 @@ impl GitBare {
         let target_branch = request.target_branch.clone();
         crate::sanitize::validate_ref_name(&target_branch)?;
         let source_revision = match request.source.and_then(|s| s.selector) {
-            Some(crate::pb::object_selector::Selector::Oid(oid)) => oid.hex.clone(),
+            Some(crate::pb::object_selector::Selector::Oid(oid)) => {
+                crate::sanitize::validate_oid_hex(&oid.hex)?;
+                oid.hex.clone()
+            }
             Some(crate::pb::object_selector::Selector::Revision(name)) => {
                 crate::sanitize::validate_revision(&name.revision)?;
                 name.revision.clone()

merge/list_merge_conflicts.rs

@@ -9,7 +9,10 @@ impl GitBare {
         request: ListMergeConflictsRequest,
     ) -> GitResult<ListMergeConflictsResponse> {
         let target = match request.target.and_then(|s| s.selector) {
-            Some(crate::pb::object_selector::Selector::Oid(oid)) => oid.hex,
+            Some(crate::pb::object_selector::Selector::Oid(oid)) => {
+                crate::sanitize::validate_oid_hex(&oid.hex)?;
+                oid.hex
+            }
             Some(crate::pb::object_selector::Selector::Revision(name)) => {
                 crate::sanitize::validate_revision(&name.revision)?;
                 name.revision
@@ -17,7 +20,10 @@ impl GitBare {
             None => return Err(GitError::InvalidArgument("target is required".into())),
         };
         let source = match request.source.and_then(|s| s.selector) {
-            Some(crate::pb::object_selector::Selector::Oid(oid)) => oid.hex,
+            Some(crate::pb::object_selector::Selector::Oid(oid)) => {
+                crate::sanitize::validate_oid_hex(&oid.hex)?;
+                oid.hex
+            }
             Some(crate::pb::object_selector::Selector::Revision(name)) => {
                 crate::sanitize::validate_revision(&name.revision)?;
                 name.revision

merge/rebase.rs

@@ -8,7 +8,10 @@ impl GitBare {
         let branch = request.branch.clone();
         crate::sanitize::validate_ref_name(&branch)?;
         let upstream_revision = match request.upstream.and_then(|s| s.selector) {
-            Some(crate::pb::object_selector::Selector::Oid(oid)) => oid.hex,
+            Some(crate::pb::object_selector::Selector::Oid(oid)) => {
+                crate::sanitize::validate_oid_hex(&oid.hex)?;
+                oid.hex
+            }
             Some(crate::pb::object_selector::Selector::Revision(name)) => {
                 crate::sanitize::validate_revision(&name.revision)?;
                 name.revision

merge/resolve_merge_conflicts.rs

@@ -11,7 +11,10 @@ impl GitBare {
         let target_branch = request.target_branch.clone();
         crate::sanitize::validate_ref_name(&target_branch)?;
         let source_revision = match request.source.and_then(|s| s.selector) {
-            Some(crate::pb::object_selector::Selector::Oid(oid)) => oid.hex,
+            Some(crate::pb::object_selector::Selector::Oid(oid)) => {
+                crate::sanitize::validate_oid_hex(&oid.hex)?;
+                oid.hex
+            }
             Some(crate::pb::object_selector::Selector::Revision(name)) => {
                 crate::sanitize::validate_revision(&name.revision)?;
                 name.revision
@@ -48,6 +51,7 @@ impl GitBare {
         command_ok(read_tree)?;
 
         for resolution in &request.resolutions {
+            crate::sanitize::validate_file_path(&resolution.path)?;
             let hash = duct::cmd(
                 "git",
                 ["--git-dir", bare.as_str(), "hash-object", "-w", "--stdin"],